From mboxrd@z Thu Jan 1 00:00:00 1970 From: nathan_lynch@mentor.com (Nathan Lynch) Date: Sun, 22 Jun 2014 22:11:58 -0500 Subject: [PATCH v7 9/9] ARM: add CONFIG_VDSO Kconfig and Makefile bits In-Reply-To: <1403493118-7597-1-git-send-email-nathan_lynch@mentor.com> References: <1403493118-7597-1-git-send-email-nathan_lynch@mentor.com> Message-ID: <1403493118-7597-10-git-send-email-nathan_lynch@mentor.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Allow users to enable the vdso in Kconfig; include the vdso in the build if CONFIG_VDSO is enabled. Signed-off-by: Nathan Lynch --- arch/arm/kernel/Makefile | 1 + arch/arm/mm/Kconfig | 15 +++++++++++++++ 2 files changed, 16 insertions(+) diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index 38ddd9f83d0e..87d4cdc3f3f9 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -86,6 +86,7 @@ obj-$(CONFIG_PERF_EVENTS) += perf_regs.o obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o perf_event_cpu.o AFLAGS_iwmmxt.o := -Wa,-mcpu=iwmmxt obj-$(CONFIG_ARM_CPU_TOPOLOGY) += topology.o +obj-$(CONFIG_VDSO) += vdso.o vdso/ ifneq ($(CONFIG_ARCH_EBSA110),y) obj-y += io.o diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig index eda0dd0ab97b..616f46794502 100644 --- a/arch/arm/mm/Kconfig +++ b/arch/arm/mm/Kconfig @@ -824,6 +824,21 @@ config KUSER_HELPERS Say N here only if you are absolutely certain that you do not need these helpers; otherwise, the safe option is to say Y. +config VDSO + bool "Enable vDSO for acceleration of some system calls" + depends on AEABI && MMU + default y if ARM_ARCH_TIMER + select GENERIC_TIME_VSYSCALL + help + Place in the process address space an ELF shared object + providing fast implementations of several system calls, + including gettimeofday and clock_gettime. Systems that + implement the ARM architected timer will receive maximum + benefit. + + You must have glibc 2.20 or later for programs to seamlessly + take advantage of this. + config DMA_CACHE_RWFO bool "Enable read/write for ownership DMA cache maintenance" depends on CPU_V6K && SMP -- 1.9.3